1. Field of the Invention
The present invention relates to a method for manufacturing an electrode of an energy storage device. Further, the present invention relates to a method for manufacturing an energy storage device.
Note that the energy storage device indicates all elements which have a function of storing energy and all devices having the element.
2. Description of the Related Art
In recent years, the development of energy storage devices such as a lithium-ion secondary battery and a lithium-ion capacitor has been conducted.
The electrode of an energy storage device is formed by forming an active material over a surface of a current collector. As the active material, a material which can adsorb and desorb ions functioning as carriers, such as carbon or silicon, is used. For example, silicon has higher theoretical capacity than carbon and is advantageous in increasing the capacity of the energy storage device. However, silicon generates stress due to volume expansion when charged, which will cause the active material to be peeled off from the current collector; accordingly, the characteristics of the energy storage device may be deteriorated by charge and discharge cycles. Thus, some techniques for mitigating the effect caused by the volume expansion of the active material have been proposed (for example, Patent Document 1).